Conflict:

diff --cc addons/base_calendar/base_calendar.py
index b51e960,64053bb..0000000
--- a/addons/base_calendar/base_calendar.py
+++ b/addons/base_calendar/base_calendar.py
@@@ -1137,11 -1135,7 +1138,15 @@@ rule or repeating pattern of time to ex
                      'email': partner.email
                  }, context=local_context)
                  if partner.email:
++<<<<<<< HEAD
 +                    mail_to = (
 +                        mail_to + ";" + partner.email
 +                        if mail_to
 +                        else partner.email
 +                    )
++=======
+                     mail_to.add(partner.email)
++>>>>>>> odoo/7.0
                  self.write(cr, uid, [event.id], {
                      'attendee_ids': [(4, att_id)]
                  }, context=context)

Reverted github.com/OCA/OCB@35aefb2c3f as https://www.ietf.org/rfc/rfc2822.txt states address-lists use a comma as separator

Commited as github.com/OCA/OCB@c1a4036bc0 by @hbrunn